The present invention has been evolved by the necessity of developing an effective and generally compact heat transfer device or condensation means for the many different types of current Rankine cycle power systems.
One of the major obstacles to achieving a practical and competitive closed cycle engine or turbine system for automobiles, is that of rejecting the large amount of heat generated within the closed loop, which ranges from approximately 3/4 million to 11/2 million BTU per hour.
The most effective, although inefficient technique presently used is utilizing large twin fans which draw in large volumes of air over conventional twin radiators, which are used as the condensing component. This "brute force" condensing expedient can consume as much as 20% of the total rated horsepower from the expander, which is unacceptable if the closed Rankine cycle is to competitively challenge the other future alternate power systems being developed.
It is becoming most evident that the conventional type of automotive radiator, or bundle of tubing and fins must be improved upon and necessary departures made to markedly increase the condensing effectiveness.
In order to reduce airflow turbulance over the heat transfer surfaces, it is an improvement to utilize an elliptical, or symmetrical airfoil shape, instead of round tubing. The finning arrangement should remain essentially unchanged, except that it will also be necessary to "micro-fin" the sheet metal shaped ducts in the direction of the airflow.